Knop Ca reactor question

[cyclgrl]

I bought my Knop C reactor used and this is the first time that I have refilled the reactor completely.

During the process, I took out a blue tube that was originally inside the reactor chamber. What is this tube for?

Here is a photo of the reactor as listed at Marine Depot:

http://www.marinedepot.com/aquarium_calcium_reactors_knop.asp?CartId=

The blue tube I am talking about can be seen within the reactor chamber. Does anyone know its purpose?

 

[cyclgrl]

It occurred to me what it was for once I thought about it. Please correct me if I'm wrong, but it's to redirect the CO2 once inside the chamber.